Water has played a critical role in the development of civilizations. The earliest civilizations developed near the Nile, Tigris, Euphrates, and Indus rivers. Access to fresh water allowed for the cultivation of crops, making a hunter-gather lifestyle obsolete. From that point onward, the vast majority of new civilizations were located near a major river, sea, or ocean. Civilizations have used water for consumption, agriculture, transportation, industry, and more.
Even in ancient times, large cities flourished on the banks of rivers. The ancient cities of Babylon, Ur, Nineveh, and Xi'an were all located on one or more rivers. In these times, rivers were both a water supply and a defense mechanism. It was difficult for armies to cross large rivers. Building along the banks of rivers allowed cities to concentrate their defenses on the portion of the city border facing inland. Water is vital for commerce and sustainability, and consequently affected the locations of many of America's largest cities. Costal cities like Boston and New York City thrived in part because they had access to goods shipped from overseas. Cities like Philadelphia and Richmond grew on navigable waterways, which provided them the same advantages enjoyed by costal cities. Upon the completion of the Erie Canal, cities on the shores of the great lakes prospered. This enabled the rapid growth of Buffalo, Cleveland, Detroit, and Chicago. New Orleans, Memphis, St. Louis, and Minneapolis are all located on the banks of the Mississippi, America's longest river. Los Angeles, San Francisco, Portland, and Seattle are all located on the Pacific Ocean. In present times, water continues to play an important role in the location of population centers. Eight of the top ten largest cities in the United States are located on or near an ocean or major river. The two exceptions, Dallas and San Antonio, contain several sizable lakes within the metropolitan area. Today, Americas 14 busiest ports are located on the coast. |